Are passive smoking, air pollution and obesity a greater mortality risk than major radiation incidents?

Smith JT - BMC Public Health (2007)

Bottom Line:
The mortality risk to populations exposed to radiation from the Chernobyl accident may be no higher than that for other more common risk factors such as air pollution or passive smoking.Radiation exposures experienced by the most exposed group of survivors of Hiroshima and Nagasaki led to an average loss of life expectancy significantly lower than that caused by severe obesity or active smoking.Population-averaged risks from exposures following major radiation incidents are clearly significant, but may be no greater than those from other much more common environmental and lifestyle factors.

Background: Following a nuclear incident, the communication and perception of radiation risk becomes a (perhaps the) major public health issue. In response to such incidents it is therefore crucial to communicate radiation health risks in the context of other more common environmental and lifestyle risk factors. This study compares the risk of mortality from past radiation exposures (to people who survived the Hiroshima and Nagasaki atomic bombs and those exposed after the Chernobyl accident) with risks arising from air pollution, obesity and passive and active smoking.

Methods: A comparative assessment of mortality risks from ionising radiation was carried out by estimating radiation risks for realistic exposure scenarios and assessing those risks in comparison with risks from air pollution, obesity and passive and active smoking.

Results: The mortality risk to populations exposed to radiation from the Chernobyl accident may be no higher than that for other more common risk factors such as air pollution or passive smoking. Radiation exposures experienced by the most exposed group of survivors of Hiroshima and Nagasaki led to an average loss of life expectancy significantly lower than that caused by severe obesity or active smoking.

Conclusion: Population-averaged risks from exposures following major radiation incidents are clearly significant, but may be no greater than those from other much more common environmental and lifestyle factors. This comparative analysis, whilst highlighting inevitable uncertainties in risk quantification and comparison, helps place the potential consequences of radiation exposures in the context of other public health risks.

Figure 3: Illustration of mortality risk from active smoking. Predicted survival curve from age 35 for smoking and non-smoking male doctors (reproduced from data presented in [6] with permission from the BMJ Publishing Group). Percentage of original population surviving is shown at each decade.

Mentions:
About half of all smokers suffer an early death from a smoking-related disease [6]. The relationship between smoking and a number of different cancers [30] and cardiovascular diseases [31] is of course well established. For example, in a 50-year study of health effects of smoking in male British doctors [6], it was shown that a 35 year old male doctor who smoked had a life expectancy approximately 10 years lower than for those doctors who had never smoked (Figure 3).

Figure 3: Illustration of mortality risk from active smoking. Predicted survival curve from age 35 for smoking and non-smoking male doctors (reproduced from data presented in [6] with permission from the BMJ Publishing Group). Percentage of original population surviving is shown at each decade.

Mentions:
About half of all smokers suffer an early death from a smoking-related disease [6]. The relationship between smoking and a number of different cancers [30] and cardiovascular diseases [31] is of course well established. For example, in a 50-year study of health effects of smoking in male British doctors [6], it was shown that a 35 year old male doctor who smoked had a life expectancy approximately 10 years lower than for those doctors who had never smoked (Figure 3).

Bottom Line:
The mortality risk to populations exposed to radiation from the Chernobyl accident may be no higher than that for other more common risk factors such as air pollution or passive smoking.Radiation exposures experienced by the most exposed group of survivors of Hiroshima and Nagasaki led to an average loss of life expectancy significantly lower than that caused by severe obesity or active smoking.Population-averaged risks from exposures following major radiation incidents are clearly significant, but may be no greater than those from other much more common environmental and lifestyle factors.

Background: Following a nuclear incident, the communication and perception of radiation risk becomes a (perhaps the) major public health issue. In response to such incidents it is therefore crucial to communicate radiation health risks in the context of other more common environmental and lifestyle risk factors. This study compares the risk of mortality from past radiation exposures (to people who survived the Hiroshima and Nagasaki atomic bombs and those exposed after the Chernobyl accident) with risks arising from air pollution, obesity and passive and active smoking.

Methods: A comparative assessment of mortality risks from ionising radiation was carried out by estimating radiation risks for realistic exposure scenarios and assessing those risks in comparison with risks from air pollution, obesity and passive and active smoking.

Results: The mortality risk to populations exposed to radiation from the Chernobyl accident may be no higher than that for other more common risk factors such as air pollution or passive smoking. Radiation exposures experienced by the most exposed group of survivors of Hiroshima and Nagasaki led to an average loss of life expectancy significantly lower than that caused by severe obesity or active smoking.

Conclusion: Population-averaged risks from exposures following major radiation incidents are clearly significant, but may be no greater than those from other much more common environmental and lifestyle factors. This comparative analysis, whilst highlighting inevitable uncertainties in risk quantification and comparison, helps place the potential consequences of radiation exposures in the context of other public health risks.